English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Molecular and Electronic Structures of Tetrahedral Complexes of Nickel and Cobalt Containing N,N‘-Disubstituted, Bulky o-Diiminobenzosemiquinonate(1−) π-Radical Ligands

Chlopek, K., Bothe, E., Neese, F., Weyhermüller, T., & Wieghardt, K. (2006). Molecular and Electronic Structures of Tetrahedral Complexes of Nickel and Cobalt Containing N,N‘-Disubstituted, Bulky o-Diiminobenzosemiquinonate(1−) π-Radical Ligands. Inorganic Chemistry, 45(16), 6298-6307. doi:10.1021/ic060242l.

Item is

Basic

show hide
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Chlopek, Krzysztof1, Author              
Bothe, Eberhard1, Author              
Neese, Frank1, Author              
Weyhermüller, Thomas1, Author              
Wieghardt, Karl1, Author              
Affiliations:
1Research Department Wieghardt, Max Planck Institute for Bioinorganic Chemistry, Max Planck Society, ou_3023881              

Content

show
hide
Free keywords: -
 Abstract: The reaction of 2 equiv of the bulky ligand N,N‘-bis(3,5-di-tert-butylphenyl)-1,2-phenylenediamine, H2[3LPDI], excess triethylamine, and 1 equiv of M(CH3CO2)2·4H2O (M = Ni, Co) in the presence of air in CH3CN/CH2Cl2 solution yields violet-black crystals of [NiII(3LISQ)2] CH3CN (1) or violet crystals of [Co(3L)2] (3). By using Pd(CH3CO2)2 as starting material, green-blue crystals of [PdII(3LISQ)2]·CH3CN (2) were obtained. Single-crystal X-ray crystallography revealed that 1 and 3 contain (pseudo)tetrahedral neutral molecules [M(3L)2] (M = Ni, Co) whereas in 2 nearly square planar, neutral molecules [PdII(3LISQ)2] are present. Temperature-dependent susceptibility measurements established that 1 and 2 are diamagnetic (S = 0) whereas 3 is paramagnetic with an S = 3/2 ground state. It is shown that 1 contains two π radical benzosemiquinonate(1−)-type monoanions, ((3LISQ)1-•, Srad = 1/2), and a central Ni(II) ion (d8; S = 1) which are antiferromagnetically coupled yielding the observed St = 0 ground state. This result has been confirmed by broken symmetry DFT calculations of 1. In contrast, the St = 3/2 ground state of 3 is more difficult to understand:  the two resonance structures [CoIII(3LISQ)(3LPDI)] ↔ [CoII(3LPDI)(3LIBQ)] might be invoked (for tetrahedral [CoII(3LISQ)2] containing an SCo = 3/2 with two antiferromagnetically coupled π-radical ligands an St = 1/2 is anticipated). Complex 2 is diamagnetic (S = 0) containing a PdII ion (d8, SPd = 0 in an almost square planar ligand field) and two antiferromagnetically coupled ligand radicals (Srad = 1/2). The electrochemistry and spectroelectrochemistry of 1,2, and 3 have been studied, and electron-transfer series comprising the species [M(L)2]z (z = 2+, 1+, 0, 1−, 2−) have been established. All oxidations and reductions are ligand centered.

Details

show
hide
Language(s): eng - English
 Dates: 2006-02-132006-07-152006-08-01
 Publication Status: Published in print
 Pages: 10
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1021/ic060242l
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Inorganic Chemistry
  Abbreviation : Inorg. Chem.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Washington, DC : American Chemical Society
Pages: - Volume / Issue: 45 (16) Sequence Number: - Start / End Page: 6298 - 6307 Identifier: ISSN: 0020-1669
CoNE: https://pure.mpg.de/cone/journals/resource/0020-1669